[PATCH 5.10 097/390] ARM: 9247/1: mm: set readonly for MT_MEMORY_RO with ARM_LPAE

From: Greg Kroah-Hartman
Date: Mon Oct 24 2022 - 12:08:09 EST


From: Wang Kefeng <wangkefeng.wang@xxxxxxxxxx>

[ Upstream commit 14ca1a4690750bb54e1049e49f3140ef48958a6e ]

MT_MEMORY_RO is introduced by commit 598f0a99fa8a ("ARM: 9210/1:
Mark the FDT_FIXED sections as shareable"), which is a readonly
memory type for FDT area, but there are some different between
ARM_LPAE and non-ARM_LPAE, we need to setup PMD_SECT_AP2 and
L_PMD_SECT_RDONLY for MT_MEMORY_RO when ARM_LAPE enabled.

non-ARM_LPAE 0xff800000-0xffa00000 2M PGD KERNEL ro NX SHD
ARM_LPAE 0xff800000-0xffc00000 4M PMD RW NX SHD
ARM_LPAE+fix 0xff800000-0xffc00000 4M PMD ro NX SHD

Fixes: 598f0a99fa8a ("ARM: 9210/1: Mark the FDT_FIXED sections as shareable")
Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
Signed-off-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/arm/mm/mmu.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 86f213f1b44b..0d0c3bf23914 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -300,7 +300,11 @@ static struct mem_type mem_types[] __ro_after_init = {
.prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
L_PTE_XN | L_PTE_RDONLY,
.prot_l1 = PMD_TYPE_TABLE,
+#ifdef CONFIG_ARM_LPAE
+ .prot_sect = PMD_TYPE_SECT | L_PMD_SECT_RDONLY | PMD_SECT_AP2,
+#else
.prot_sect = PMD_TYPE_SECT,
+#endif
.domain = DOMAIN_KERNEL,
},
[MT_ROM] = {
--
2.35.1